NSIDC Data Announcementshttp://nsidc.org/the-drift
News and Tips for NSIDC Data UsersFri, 31 Jul 2015 21:10:31 +0000en-UShourly1http://wordpress.org/?v=4.2.2Zoom In: Geolocating IceBridge Datahttp://nsidc.org/the-drift/2015/05/zoom-in-geolocating-icebridge-data/
http://nsidc.org/the-drift/2015/05/zoom-in-geolocating-icebridge-data/#commentsThu, 14 May 2015 22:04:47 +0000http://nsidc.org/the-drift/?p=1948Read more »]]>In 2009, NASA initiated Operation IceBridge, flying airborne missions to pinch hit for the ICESat satellites’ expected gap from 2009 to 2016. The airborne platform and the broad suite of instrumentation allow for the collection of high resolution snow and ice data from targeted areas of scientific interest. The downside is that the total area covered is not nearly as vast as what a satellite typically covers.

The resources listed below allow you to zoom in on the specific areas of the Earth where IceBridge data were collected. Many of these resources also provide a handy way to access the IceBridge data of your choice.

]]>http://nsidc.org/the-drift/2015/05/zoom-in-geolocating-icebridge-data/feed/0All About SMAP Data: Upcoming Webinarhttp://nsidc.org/the-drift/2015/05/smap-webinar/
http://nsidc.org/the-drift/2015/05/smap-webinar/#commentsTue, 05 May 2015 15:28:40 +0000http://nsidc.org/the-drift/?p=2038Read more »]]>With the launch of the Soil Moisture Active Passive (SMAP) spacecraft and deployment of its instruments earlier this year, the long awaited NASA SMAP Mission is upon us and the NASA NSIDC DAAC will be distributing SMAP soil moisture, freeze/thaw, and carbon data in the coming months. Please join us in the upcoming NASA Earthdata Webinar “NASA’s Soil Moisture Active Passive Mission Data Products” on 14 May 2015, where the content and format of SMAP data will be presented.

The global, high-resolution data provided by SMAP will enable and enhance research and applications to:

We have recognized that it can be challenging to differentiate between data sets and determine which are most useful and relevant to your applications. In response to this, the NSIDC DAAC has been developing a data set search tool with your needs and preferences in mind. Web metrics and usability studies have been used to answer the following questions:

How do users search for data?

Which data attributes are of primary importance when selecting a data set?

When similar data sets exist, how is one chosen over another?

We have found that data set differentiation is driven by both what we present and how we present it. The “what” can range from relatively straightforward information such as the measured parameter or the spatial coverage to the more complex and nuanced information such as data usage suggestions or data usage metrics. The “how” includes considerations such as making data set information scannable and comparable to tailoring relevance ranking algorithms to match user expectations.

During the webinar, not only will you get an introduction to the NSIDC Data Search tool, you will also be able to ask questions or provide feedback about the tool.

]]>http://nsidc.org/the-drift/2015/04/join-the-upcoming-webinar-for-more-information-about-nsidc-data-search/feed/0Why a DOI?http://nsidc.org/the-drift/2015/02/why-a-doi/
http://nsidc.org/the-drift/2015/02/why-a-doi/#commentsThu, 19 Feb 2015 00:14:49 +0000http://nsidc.org/the-drift/?p=1705Read more »]]> Recent data announcements rolling off of the virtual presses at NSIDC have included some new information: the DOI, or Digital Object Identifier associated with a data set. Decoding a DOI is a simple task and understanding its applications can be useful to the scientific research community.

The establishment of the DOI system was led by the non-profit International DOI Foundation (IDF). The system was approved by the International Organization for Standardization (ISO) in 2010, which requires that DOI generation follow ISO standard 26324-2012. This standard states that DOIs can be assigned to any form of physical or digital content as a permanent and discoverable reference to the object. Look for them commonly assigned to journal articles, images, broadcast media, software, or as utilized by NSIDC, data sets.

The anatomy of a DOI includes a prefix that always begins with ‘10,’ indicating that the ID is a DOI. The second part of the prefix is typically four digits and identifies the registered holder of the DOI. For example, the four digit identifiers for NSIDC and NASA ESDIS, (which encompasses the NASA DAAC at NSIDC), are 10.7265 and 10.5067, respectively. The remainder of the code is generated by the owner of the DOI and may follow a personal convention. For DOIs assigned to NASA ESDIS data holdings, the rest of the DOI string will include the mission or program and data set ID.

Utilizing the EZID curation center at the University of California as its registration agency, NSIDC generated its first DOIs in 2012 for the World Glacier Inventory (doi:10.7265/N5/NSIDC-WGI-2012-02) and the Glacier Photograph Collection (doi:10.7265/N5/NSIDC-GPC-2009-12), followed by GLAS HDF5 data (doi:10.5067/ICESAT/GLAS/DATA125). Many data sets released at NSIDC have since followed suit.

DOIs are now included in NSIDC data citation suggestions where they are available. We encourage you to include them in your references. Besides providing a permanent identifier for the data set, new promising applications of DOIs in data discovery, cross referencing, and metadata management are emerging.

]]>http://nsidc.org/the-drift/2015/02/why-a-doi/feed/0Why do the AMSR-E L3 Soil Moisture data values seem so high?http://nsidc.org/the-drift/2015/02/why-do-the-amsr-e-l3-soil-moisture-data-values-seem-so-high/
http://nsidc.org/the-drift/2015/02/why-do-the-amsr-e-l3-soil-moisture-data-values-seem-so-high/#commentsTue, 17 Feb 2015 21:36:09 +0000http://nsidc.org/the-drift/?p=1883As noted on the Data Fields Web page, the soil moisture data are scaled. Thus, you will need to multiply the data by 0.001 to obtain soil moisture in g cm-3.
]]>http://nsidc.org/the-drift/2015/02/why-do-the-amsr-e-l3-soil-moisture-data-values-seem-so-high/feed/0Will NSIDC be at AGU?http://nsidc.org/the-drift/2014/12/will-nsidc-be-at-agu/
http://nsidc.org/the-drift/2014/12/will-nsidc-be-at-agu/#commentsFri, 12 Dec 2014 21:52:34 +0000http://nsidc.org/the-drift/?p=1815Read more »]]>Yes. NSIDC will have a booth in the exhibit hall (#2444) where you can speak with NSIDC staff, gather information on our data holdings, and pick up some souvenirs. Several NSIDC staff will also be presenting their research through posters and talks.
]]>http://nsidc.org/the-drift/2014/12/will-nsidc-be-at-agu/feed/0Watch, Listen & Read – New Software Player for Inuit Videoshttp://nsidc.org/the-drift/2014/11/watch-listen-read-new-software-player-for-inuit-videos/
http://nsidc.org/the-drift/2014/11/watch-listen-read-new-software-player-for-inuit-videos/#commentsFri, 07 Nov 2014 20:45:55 +0000http://nsidc.org/the-drift/?p=1718Read more »]]>Have you ever wondered about how narwhal tastes different from beluga? Now you can learn about this and more through interviews with Inuit hunters. And you don’t even have to know Inuktitut. With a new feature released by the Exchange for Local Observations and Knowledge for the Arctic (ELOKA) team, the English translations of many interviews with Inuit elders and hunters are integrated alongside the video presentation. These interviews highlight the research conducted by the Narwhal Tusk Research Project in Baffin Bay.

Above: Screenshot of the ELOKA web site playing an interview with hunter Cornelius Nutarak.

]]>http://nsidc.org/the-drift/2014/11/watch-listen-read-new-software-player-for-inuit-videos/feed/0What is the difference between smoothed and unsmoothed data in the AE_L2A data set, and how should I use them together?http://nsidc.org/the-drift/2014/08/what-is-the-difference-between-smoothed-and-unsmoothed-data-in-the-ae_l2a-data-set-and-how-should-i-use-them-together/
http://nsidc.org/the-drift/2014/08/what-is-the-difference-between-smoothed-and-unsmoothed-data-in-the-ae_l2a-data-set-and-how-should-i-use-them-together/#commentsThu, 28 Aug 2014 19:54:16 +0000http://nsidc.org/the-drift/?p=1657Read more »]]>Each frequency is looking at a different size footprint. Each frequency has its own feedhorn, and is thus susceptible to independent pointing errors. The most important benefit of resampling (or smoothing) is to create a suite of frequencies that are all looking at the same scene. So, when the higher-resolution channels are resampled to match the footprints of the lower-resolution channels, the data are smoothed.

In the not-resampled (unsmoothed) channels (denoted by ‘o‘ in Table 5):

The unsmoothed 23.8 GHz channel does not spatially correlate with any other channels, and should generally not be used in conjunction with any other frequencies

The 18.7, 36.5, and 89.0 GHz channels are not resampled to their own footprints, because it is intended that they be used in their native (not-resampled) form

The 89A and 89B GHz channels are not aligned with the lower-resolution channels, by design

Pointing errors in the 6.9 and 10.7 GHz channels led to resampling of these channels to their own footprints in order to line their boresights up (or spatially correlate) with the higher-resolution channels

The 23.8 GHz channel is resampled to spatially correlate with the 7.9, 10.7, and 18.7 GHz channels (it was determined that the footprint size of the 23.8 GHz channel was close enough to that of 18.7 that it did not warrant a suite of channels spatially correlated to the native 23.8 GHz footprint)

For 18.7 and 36.5, each higher frequency is resampled to correlate with those native footprints

The unsmoothed and smoothed channels (see Table 5) are useful for constructing sets of “spatially correlated” channels, such as:

Over homogeneous areas of ocean, the different size footprint observed by each frequency is not a big problem. But if there is heterogeneous meteorology, each channel may be looking at different amounts of cloud, rain, land, etc.

Start with the lowest frequency (largest footprint) that is important to any particular application.

For example, 10.7 GHz wind speed retrieval. Then ask, what would 18.7 GHz say if it were looking at the exact same patch of earth as this 10.7 GHz observation? And how bright would this exact same patch of earth (“scene”) be at 36.5 GHz?

The unsmoothed 18.7 and 36.5 GHz channels do not answer these questions directly, but there are more than enough observations to construct “virtual” observations which do “measure” the same scene. These are the smoothed channels.

]]>http://nsidc.org/the-drift/2014/08/what-is-the-difference-between-smoothed-and-unsmoothed-data-in-the-ae_l2a-data-set-and-how-should-i-use-them-together/feed/0Help improve tools and services at NSIDC DAAChttp://nsidc.org/the-drift/2014/08/help-improve-tools-and-services-at-nsidc-daac/
http://nsidc.org/the-drift/2014/08/help-improve-tools-and-services-at-nsidc-daac/#commentsWed, 27 Aug 2014 20:46:54 +0000http://nsidc.org/the-drift/?p=1633Read more »]]>The NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) is one of twelve NASA Earth Observing System Data and Information System (EOSDIS) data centers. Several of the data sets distributed by NSIDC are part of the DAAC, including but not limited to MODIS, GLAS, AMSR-E, ICEBridge, and SSM/I. If you use one or several of these data sets, we’d like to hear what you think.

During September 2014, registered NSIDC DAAC data users will receive an email invitation from Claes Fornell International (CFI) Group on behalf of NASA to participate in a Web-based survey about the quality and usability of NSIDC DAAC tools and services. This email will be coming from ‘qualtrics-survey.com‘. Please check your spam filters to allow ‘qualtrics-survey.com‘.

If you receive the survey, please fill it out. It takes approximately ten minutes to complete the anonymous questionnaire. Optional comment fields are provided for additional feedback. Feedback from previous surveys has been used to guide development of NSIDC DAAC tools and services, such as NSIDC Data Search.